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package x509
import (
"fmt"
"reflect"
"testing"
"github.com/zmap/zcrypto/encoding/asn1"
"github.com/zmap/zcrypto/x509/pkix"
)
// TestParseTorServiceDescriptorSyntax tests that parsing certificates with the
// CAB Forum TorServiceDescriptorSyntax x509 extension works correctly.
func TestParseTorServiceDescriptorSyntax(t *testing.T) {
// expected TorServiceDescriptorHash hash bytes from test certs.
mockHashBytes := []byte{
0xc7, 0x49, 0xf5, 0xb2, 0x49, 0x9c, 0x8f, 0x65,
0x5c, 0x19, 0xb3, 0x3f, 0xf9, 0x3e, 0x03, 0x7b,
0x7b, 0x7d, 0xbe, 0x47, 0x2a, 0xac, 0x62, 0x78,
0x30, 0x71, 0xb0, 0x39, 0xb8, 0x66, 0x38, 0x5c,
}
mockAlgorithm := pkix.AlgorithmIdentifier{
Algorithm: asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 1},
}
// mustASN1 marshals a given object to its ASN1 bytes or panics.
mustASN1 := func(value interface{}) []byte {
result, err := asn1.Marshal(value)
if err != nil {
panic(fmt.Sprintf("err marshaling asn1 test data: %v", err))
}
return result
}
// sequence marshals a ASN1 SEQUENCE for the given bytes.
sequence := func(bytes []byte) []byte {
return mustASN1(asn1.RawValue{
Tag: asn1.TagSequence,
Class: asn1.ClassUniversal,
IsCompound: true,
Bytes: bytes,
})
}
// torServiceDescriptorHash constructs a marshaled SEQUENCE for
// a TorServiceDescriptorHash with the given values.
torServiceDescriptorHash := func(onion string, algorithm pkix.AlgorithmIdentifier, hash []byte, bits int) []byte {
return sequence(
append(mustASN1(asn1.RawValue{
Tag: asn1.TagUTF8String,
Class: asn1.ClassUniversal,
Bytes: []byte(onion),
}),
append(
mustASN1(algorithm),
mustASN1(asn1.BitString{
Bytes: hash,
BitLength: bits,
})...)...,
))
}
testCases := []struct {
Name string
InputExtension pkix.Extension
ExpectedErrMsg string
ExpectedTorServiceDescriptors []*TorServiceDescriptorHash
}{
{
Name: "empty Tor service descriptor extension",
InputExtension: pkix.Extension{
Value: nil,
},
ExpectedErrMsg: "asn1: syntax error: unable to unmarshal outer TorServiceDescriptor SEQUENCE",
},
{
Name: "invalid outer SEQUENCE in service descriptor extension",
InputExtension: pkix.Extension{
Value: mustASN1(asn1.RawValue{}),
},
ExpectedErrMsg: "asn1: syntax error: invalid outer TorServiceDescriptor SEQUENCE",
},
{
Name: "data trailing outer SEQUENCE in service descriptor extension",
InputExtension: pkix.Extension{
Value: append(
sequence(nil), // Outer SEQUENCE
mustASN1(asn1.RawValue{})..., // Trailing data
),
},
ExpectedErrMsg: "asn1: syntax error: trailing data after outer TorServiceDescriptor SEQUENCE",
},
{
Name: "bad service descriptor onion URI field tag",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
sequence( // TorServiceDescriptorHash SEQUENCE
mustASN1(asn1.RawValue{}), // Invalid Onion URI
)),
},
ExpectedErrMsg: "asn1: syntax error: TorServiceDescriptorHash missing non-compound UTF8String tag",
},
{
Name: "bad service descriptor algorithm field",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
sequence( // TorServiceDescriptorHash SEQUENCE
mustASN1(asn1.RawValue{ // Onion URI
Tag: asn1.TagUTF8String,
Class: asn1.ClassUniversal,
}))),
// No pkix.AlgorithmIdentifier algorithm field
},
ExpectedErrMsg: "asn1: syntax error: error unmarshaling TorServiceDescriptorHash algorithm",
},
{
Name: "bad service descriptor hash field",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
sequence( // TorServiceDescriptorHash SEQUENCE
append(mustASN1(asn1.RawValue{ // Onion URI
Tag: asn1.TagUTF8String,
Class: asn1.ClassUniversal,
}),
mustASN1(mockAlgorithm)...), // Algorithm
)),
// No BitString hash field
},
ExpectedErrMsg: "asn1: syntax error: error unmarshaling TorServiceDescriptorHash Hash",
},
{
Name: "data trailing inner TorServiceDescriptorHash SEQUENCE",
InputExtension: pkix.Extension{
Value: sequence(
sequence( // Outer SEQUENCE
append(mustASN1(asn1.RawValue{ // Onion URI
Tag: asn1.TagUTF8String,
Class: asn1.ClassUniversal,
}),
append(
append(
mustASN1(mockAlgorithm), // Algorithm
mustASN1(asn1.BitString{ // Hash
Bytes: []byte{0x00},
BitLength: 1,
})...,
),
mustASN1(asn1.RawValue{})..., // Trailing data
)...,
),
)),
},
ExpectedErrMsg: "asn1: syntax error: trailing data after TorServiceDescriptorHash",
},
{
Name: "valid service descriptor unknown hash algorithm",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
torServiceDescriptorHash(
"https://zmap.onion",
pkix.AlgorithmIdentifier{
Algorithm: asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 99},
},
mockHashBytes,
256),
),
},
ExpectedTorServiceDescriptors: []*TorServiceDescriptorHash{
{
Onion: "https://zmap.onion",
AlgorithmName: "Unknown",
Algorithm: pkix.AlgorithmIdentifier{
Algorithm: asn1.ObjectIdentifier{2, 16, 840, 1, 101, 3, 4, 2, 99},
},
HashBits: 256,
Hash: mockHashBytes,
},
},
},
{
Name: "valid service descriptor extension",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
torServiceDescriptorHash(
"https://zmap.onion",
mockAlgorithm,
mockHashBytes,
256),
)},
ExpectedTorServiceDescriptors: []*TorServiceDescriptorHash{
{
Onion: "https://zmap.onion",
AlgorithmName: "SHA256",
Algorithm: mockAlgorithm,
HashBits: 256,
Hash: mockHashBytes,
},
},
},
{
Name: "valid service descriptor extension, multiple entries",
InputExtension: pkix.Extension{
Value: sequence( // Outer SEQUENCE
append(torServiceDescriptorHash(
"https://zmap.onion",
mockAlgorithm,
mockHashBytes,
256),
torServiceDescriptorHash(
"https://other.onion",
mockAlgorithm,
mockHashBytes,
256)...),
)},
ExpectedTorServiceDescriptors: []*TorServiceDescriptorHash{
{
Onion: "https://zmap.onion",
AlgorithmName: "SHA256",
Algorithm: mockAlgorithm,
HashBits: 256,
Hash: mockHashBytes,
},
{
Onion: "https://other.onion",
AlgorithmName: "SHA256",
Algorithm: mockAlgorithm,
HashBits: 256,
Hash: mockHashBytes,
},
},
},
}
for _, tc := range testCases {
t.Run(tc.Name, func(t *testing.T) {
descs, err := parseTorServiceDescriptorSyntax(tc.InputExtension)
if err != nil && tc.ExpectedErrMsg == "" {
t.Errorf("expected no error, got %v", err)
} else if err == nil && tc.ExpectedErrMsg != "" {
t.Errorf("expected error %q, got nil", tc.ExpectedErrMsg)
} else if err != nil && err.Error() != tc.ExpectedErrMsg {
t.Errorf("expected error %q, got %q", tc.ExpectedErrMsg, err.Error())
} else if err == nil && tc.ExpectedErrMsg == "" {
if len(descs) != len(tc.ExpectedTorServiceDescriptors) {
t.Errorf("expected %d TorServiceDescriptorHashes, got %d",
len(tc.ExpectedTorServiceDescriptors), len(descs))
}
for i, servDesc := range descs {
if !reflect.DeepEqual(servDesc, tc.ExpectedTorServiceDescriptors[i]) {
t.Errorf("expected TorServiceDescriptors %#v in index %d, got %#v",
tc.ExpectedTorServiceDescriptors[i], i, servDesc)
}
}
}
})
}
}
|
